Bed springs for beds are generally constructed of a rigid base frame comprised of wood and a wire grid frame supported in substantially spaced, parallel relation to the base frame by a plurality of longitudinally and transversely-spaced rows of spring units which may be in the form of coils of wire or in the form of bent wire or a combination thereof attached at their lower ends to the base frame and at their upper ends to the grid frame. It is the purpose of this invention to provide spring units of the bent wire type of improved construction for use exclusively or in combination with coil spring units structured to provide soft, relatively deep controlled yield without the sacrifice of stability, as opposed to yield which is stiffly resistant to displacement and, hence, not conductive to comfort.